What is the Trinity?

Is there but one God?¹

Yes; there is but one God.

Why can there be but one God?²

There can be but one God, because God, being supreme and infinite, cannot have an equal.

How many persons are there in the Godhead?³

There are three persons in the Godhead, the Father, the Son, and the Holy Spirit; and these three are one God, the same in essence, equal in power and glory. (1 Corinthians 8:6; John 10:30; John 14:9; Acts 5:3-4; Matthew 28:19; 2 Corinthians 13:14)

Since there is no God but one, why do you here mention three, the Father, Son, and Holy Spirit?⁴

Because in the one essence of God, it behooves us to look on God the Father as the beginning and origin, and the first cause of all things; next the Son, who is his eternal Wisdom; and, lastly, the Holy Spirit, as his energy diffused indeed over all things, but still perpetually resident in himself.

How are the three divine persons distinguished from each other?⁵

The Father has begotten the Son from eternity; the Son is begotten of the Father from eternity; the Holy Spirit from eternity proceeds from the Father and the Son. To the Father especially is ascribed the work of creation; to the Son, the work of redemption; to the Holy Spirit, the work of sanctification. (Psalm 2:7; John 15:26; Galatians 4:6)

Why is the first person of the Trinity called “the Father”?⁶

God is the Father of my Lord Jesus Christ and also my Father through faith in Christ. (Matthew 3:17; John 20:17; Galatians 3:26)

He is also the Father of all people because He created them. Strictly speaking, there is only one human race, because all human beings are equally the children of Adam and Eve and are equally redeemed by Christ. (Malachi 2:10)

How does it appear that the Son and the Holy Ghost are God equal with the Father?⁷

The Scriptures manifest that the Son and the Holy Ghost are God equal with the Father, ascribing unto them such names, attributes, works, and worship, as are proper to God only.

Can we fully understand how the three Divine Persons are one and the same God?⁸

We cannot fully understand how the three Divine Persons are one and the same God, because this is a mystery.

Footnotes

1. Baltimore Larger Catechism (1885), Question 21.
2. Baltimore Larger Catechism (1885), Question 22.
3. Baptist Catechism (1677), Question 10.
4. Geneva Catachism (1545), Question 19.
5. Luther’s Small Catechism (1529), Question 95.
6. Luther’s Small Catechism (1529), Question 96.
7. Westminster Larger Catechism (1647), Question 11.
8. Baltimore Larger Catechism (1885), Question 30.